The issue does not occur anymore. It has been fixed, but not completely satisfactory, by a workaround in the kernel to use an older backlight control method than one comparable to Windows 8 which provides a more finegraned control. All in all backlight control support is back to the level of quantal in raring and saucy: functional.
I just tried to install the 2.57 update, but the updater told me that I already have the latest version. $ sudo dmidecode -s bios-version && sudo dmidecode -s bios-release-date G4ET97WW (2.57 ) 10/17/2013 -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1173984 Title: 8086:0166 [Lenovo ThinkPad T530] Backlight control via fn-keys is stuck in certain ranges To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1173984/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
